Injector device with dosage selector



April 7, 1970 F. PARIS! INJECTOR DEVICE WITH DOSAGE SELECTOR 3 Sheets-Sheet 1 Filed March 17, 1969 I NVEN TOR. FRED PA R/S/ April 7, 1970 F. PARISI INJECTOR DEVICE WITH DOSAGE SELECTOR 3 Sheets-Sheet 2 Filed March 17, 1969 INVENTOR. FRED PAR/S/ BY 4% ATTORNEY April 7, 1970 F. PARISI INJECTOR DEVICE WITH DOSAGE SELECTOR 3 Sheets-Sheet 3 Filed March 17, 1969 FIG-8 ATTORNEY United States Patent 3,504,673 INJECTOR DEVICE WITH DOSAGE SELECTOR Fred Parisi, New Haven, Conn., assignor to E. R. Squibb & Sons, Inc., New York, N.Y., a corporation of Delaware Continuation-impart of application Ser. No. 664,019, Aug. 29, 1967, which is a continuation-in-part of application Ser. No. 488,978, Sept. 21, 1965. This application Mar. 17, 1969, Ser. No. 813,797

Int. Cl. A61m /24 US. Cl. 128218 7 Claims ABSTRACT OF THE DISCLOSURE A manually operated injector device useful in introducing predetermined quantities of fluid, e.g., pharmaceuticals into animals having a semicylindrical holder for a capsule of medicinal fluid, a trigger contained in a pistol grip for advancing a rack and rack driver, and a dosage selector which is effective to control the stroke of the rack and thereby the dosage amount which is injected.

This application is a continuation-in-part of my US. application Ser. No. 664,019 filed Aug. 29, 1967, which is a continuation-in-part of my U.S. application Ser. No. 488,978, filed Sept. 21, 1965, both now abandoned.

In general, the injector device of the present invention relates to the so-called gun type injectors embracing a barrel member and a pistol grip including a trigger device.

A particular feature of the present invention is the provision of an improved hand-operated hypodermic gun.

Prior art dispensing guns or injectors of the general class to which the present invention relates usually include a barrel member detachably connected to a pistol grip and trigger assembly; normally the barrel is detached to receive a capsule of medicinal fluid. The capsule is fitted with a resilient or rubber-like plug or stopper at each end. One end of the barrel makes a connection with a hypodermic needle which communicates with the interior of the capsule through one capsule plug. The other end of the barrel abuts a piston head fixed to a ram or piston.

The ram is indexed or moved, in step-by-step fashion, in response to the operation of the trigger to drive the second plug through the capsule toward the hypodermic needle to create sufiicient hydraulic pressure within the capsule to dispense fluid for hypodermic injection.

A special feature of the present invention is the provision of an injector gun wherein the pistol grip and barrel are fixed.

A further feature of the invention is the provision of an injector gun into which it is possible to insert a capsule of medication without dismantling the gun.

A still further feature of the invention is the provision of a novel dosage selector device.

A further feature of the invention is the provision of a novel ram or rack and rack driver assembly in combination with a novel leaf spring arrangement.

A gun type fluid injector device of the type having a barrel and pistol grip assembly embracing certain principles of the present invention may comprise a semicylindrical barrel structure fixed to the pistol grip where the barrel is of sufficient length to receive a capsule of fluid while the pistol grip remains connected to the barrel, a rack, a cooperating rack driver, a leaf spring assembly for controlling the cooperation of the rack and rack driver, and a dosage selector cooperating with the rack driver.-

Patented Apr. 7, 1970 Other features of the present invention will become more apparent from the succeeding specification when read in conjunction with the appended drawings in which:

FIG. 1 is a side elevational view with certain portions shown in section for clarity of an injector device illustrating one embodiment of the invention;

FIG. 2 is a plan view of FIG. 1;

FIG. 3 is a plan view of the dosage selector of FIG. 1 as viewed from section line 33;

FIG. 4 is a vertical section of FIG. 1 along section line 44 viewed in the direction shown by the arrows;

FIG. 5 is a perspective, exploded view of the leaf spring assembly;

FIG. 6 is a sectional view of the barrel of FIG. 1 taken along 66;

FIG. 7 is a side view of the representation of FIG. 1 disclosing the exterior structure; and

FIG. 8 is a plan view of a modified dosage selector of FIG. 1.

Referring now in detail to the drawings, a pistol grip P hingedly supports a trigger T powdered by coil spring C in well known fashion. A barrel B is rigidly connected to the pistol grip P and supports a hypodermic needle H by means of a threaded cap F.

A capsule of medicinal fluid M is disposed in the barrel B.

Note that the barrel B is formed in the shape of a semicylinder 10 (see FIG. 6) terminating at one end in a raised wall portion 11 projecting radially beyond the diameter of the capsule M.

The opposite end of the semicylindrical barrel 11 terminates at a shoulder 12 formed integrally with a receiver 13.

The reference numerals 14 and 16 designate cutouts or finger holds to facilitate loading and unloading a capsule.

As is most apparent in FIGS. 1 and 7, the Wall portion 11 and the shoulder 12 operate to protect the capsule M from damage in the event the injector device is accidentally dropped.

The forward end of the capsule is fitted with a resilient stopper or plug 17 operative to make a fluid-tight connection with the hypodermic needle H. The needle pierces the plug 17 upon insertion of the capsule thus providing a fluid conduit from the interior of the capsule to the needle.

The opposite end of the capsule M is provided with a second stopper or plug 18 making face-to-face contact with piston head 19 in turn connected to rack 21 mounted for sliding motion in guide slot 22 of the receiver (see FIG. 4).

The rack 21 is formed with a plurality of teeth 23 each having a driving face 24 and a ratched face 26.

The driving faces of teeth 2323 are engageable with complementary teeth 27 formed on a rack driver 28.

In the arrangement shown in FIG. 1, a group of teeth 27-27 formed on the rack driver 28, are shown in op- ,erative engagement with corresponding teeth 2323 formed on rack 21 so that the operation or motion of the driver 28 horizontally to the left is effective to drive the rack to the left while operation in the reversed direction permits racheting action.

The rack driver is formed with a recess 29 which receives a lug 31 formed as an extension to trigger T.

A leaf spring assembly, indicated generally by reference numeral 32 (see FIGS. 1 and 5) comprising a primary leaf 33 and a secondary leaf 34, is rigidly fixed to pistol grip .P by means of a stud 36. The primary leaf 33 is formed with a cutout or opening 35 to provide a guide or track for the rack driver 28 and to limit the backward stroke of the rack driver.

Referring to FIG. 1, note that the coil spring C tends to drive the trigger T in a clockwise direction about hinge pin 37 in turn urging the rack driver to the right until rear face 38 of the rack driver contacts the right end of slot 35 as at 39.

Referring to FIGS. 4 and 5, it is apparent that straps 41 and 42 of primary leaf spring 33 straddle the rack driver 28 and are disposed immediately above rack driver shoulders 43 and 44.

The forward or left end of primary leaf spring 33 is formed with an operating lug 46 which is operable to depress spring 33, against its normal tendency to move vertically upward, effective to cause straps 41 and 42 to move downwardly into engagement with corresponding shoulders 43 and 44 effective to break the driving connection between teeth 23 and 27 of the rack and rack driver, respectively.

The primary leaf spring 33 is also formed with a cutout 50 operative to engage rack teeth 2323 as at 63 to block motion of the rack to the right but allowing motion of the rack to the left.

Secondary leaf spring 34, engaging the under side of rack driver 28, is utilized to drive this member upwardly into engagement with the rack.

The left end of the secondary spring 34 is formed with a slot 40 defining a pair of webs 47 and 48 to provide clearance for the upper end of the dosage selector which will become more apparent as the specification proceeds.

Referring now to FIGS. 1, 2, 3 and 8, a dosage selector device, indicated generally at 60 in FIG. 1, including a knurled selector knob 49 and a selector head or irregular cam 51 and 151, is formed with an undercut or neck portion 52 and 152 having a square pentagonal or other configuration cross section in accordance with the number of doses to be delivered and is held in the receiver by a detent 54.

The detent 54 slides between shoulders 56 and 57 of the dosage selector to retain the selector in place within the receiver and also serves to insure that the selector head is rotatable with a reasonable amount of friction while having ability to retain or hold a desired setting.

The dosage selector 49 is movable in 90 increments to 4 positions corresponding to 4 different dosages labeled 0, 1, 2, and in FIG. 3. The dosage selector 49 can also be made movable to 72, 60 or other increments depending upon the number of separate desired doses.

The selector head 51 is a raised boss or lug generally defining a sector of a circle in cross-section. The head is positioned in the path of the rack driver 28 so as to limit the motion of the rack driver to the left (and thus the motion of the rack) to control dosage.

For example, when the selector head 51 is in the position shown in FIG. 3, denoting a dosage of 1 cc., the head is in position to block motion of the rack driver to the left when face 59 of the head encountered the mating face 70 of the rack driver.

Correspondingly, when the selector head is rotated so that the face thereof, corresponding to the numeral 2, is in blocking position, the rack driver is free to move to the left and additional increment to inject a 2 cc. dosage.

When the selector knob is rotated to the position represented by the reference numeral 5, the selector head 51 is so positioned relative to the rack driver that the head is in alignment with a slot 61 (see FIGS. 3 and 4) so that the rack driver is free to ride over the selector head 51 and blocking action does not occur until the curved surface referenced by numeral 5 engages shoulder 62.

Modified selector head 151 is similar in construction to selector head 51 except that it can provide for from 1 to about 5 different dosages. The amount of each dose may be varied as desired by placing the proper indentation head 151 (to provide an irregular cam) and/or changing the size of rack driver recess 29 or rack driver 28. For example, the rack driver 28 may be positioned in such a manner that its forward motion is topped by the round edge of head 151 illustrated as 1 on squeezing trigger T, then rotating knob 60' an increment of 72 so that at notch 2 rack driver 28 stops at a different position allowing the plunger 18 to be driven further into the cartridge. Other notches 3', 4' and 5 are illustrated and can be leveled or notched to desired requirements so that a predetermined dose at each notch can be delivered. Notch 2' may also be modified by extending outward so as to allow for delivery of half the amount of notch 1' if so desired.

Obviously, the zero position designates a no dosage position.

OPERATION Assuming that a capsule M containing medicinal fluid is disposed in the semicylindrical barrel B with hypodermic needle H providing a fluid conduit to the interior of the capsule, one operates the trigger T to compress spring C effective to pivot the trigger about pin 37.

This action will cause head 31 to move the rack driver to the left in turn driving the rack to the left to move plug 18 into the capsule M.

Fluid pressure developed within the capsule by virtue of the motion just described is eifective to discharge a selected dosage through the hypodermic needle H.

The stroke of the rack driver 28 is controlled by the setting of the dosage selector head 51 to limit motion of the plug 18 consistent with the selected dosage.

Obviously, the size and number of teeth on the rack including its mating rack driver and the configuration of the selector head 51 can be designed and varied in a number of ways depending upon the range and size of dosage desired.

When the trigger T is released, spring C is operative to permit rack driver to rachet to the right coming to rest when wall 38 engages the right end of slot 34 as at 39.

During the racheting action of the rack driver 28, the left end of the primary leaf spring 34 is operative to engage the driving face of a rack tooth as at 63 to hold the rack motionless during the return stroke of the rack driver.

Obviously, the trigger T is operative in sequential or cyclic fashion to inject a series of doses of the same or different size (depending upon the selector setting) by repeating the operation just described.

When the movable plug 18 is driven to the left into contact with the plug 17 (see dotted line position) having expelled all medicinal fluid from the capsule, the rack may be returned to the right by depressing lug 46 to disengage the left end of the primary leaf spring 33 from engagement from the teeth of the rack. Thereafter, the rack is freely movable to the right by grasping operating lug 66 and applying force to the right.

It is anticipated that a Wide variety of embodiments of the present invention may be devised without departing from the spirit and scope of the invention.

What is claimed is:

1. A gun-type hypodermic injector device comprising a barrel and pistol grip assembly wherein the barrel structure is semicylindrical and fixed to the pistol grip, the barrel having a suflicient length to receive :a capsule containing a pharmaceutical formulation while the pistol grip remains connected to the barrel, a rack and a cooperating rack driver in operative relation within the barrel trigger means for advancing the rack driver, a leaf spring assembly for controlilng the cooperation of the rack and rack driver, and a dosage selector means coopcrating with the rack driver which is effective to control the stroke of the rack and thereby the dosage amount which is injected, said leaf assembly wherein the primary leaf assembly guides the rack and limit its backward stroke.

2. A gun of claim 1 wherein the primary leaf is in operable relation with the rack and the secondary leaf is in operable relation with the rack driver.

3. A gun in accordance with claim 2 wherein the pri mary leaf is operable in a vertical direction against the rack.

4. A gun in accordance with claim 1 wherein the trigger means actuates the rack driver horizontally.

5. A gun in accordance with claim 1 wherein the dosage selector means is a cam that interferes with the horizontal movement of the rack driver.

6. A gun in accordance with claim 5 wherein the cam is irregular.

7. A gun in accordance with claim 6 wherein the primary and secondary leaf springs cooperate to limit the backward movement of the rack driver.

6 References Cited UNITED STATES PATENTS RICHARD A. GAUDET, Primary Examiner M. F. MAJESTIC, Assistant Examiner US. Cl. X. R.

Patent No.

Inventofls) Dated April 7, 1970 Fred Parisi It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shovm below:

Column 4,

( Atteat:

Edward M. Fletcher, In Attesting Officer line 68, "controlilng" should be controll ing and line 72, after "assembly" and before "wherein" insert having a primary and secondary leaf assembly SI'GNED KND SEALED JUL28B70 WILLIAM E. 'SGHUYLER, JR. Commissioner of Patents 

